Device for burning atomized liquid fuel



I DEVICE FOR BUNING ATOMIZED LIQUID FUELI ATT-ORNEY.

vJun'14, 1938. I A. BARGEBQER `2,120,387

DEVICE FOR BURNING ATOMIZED LIQUID FUEL INVENTOR BY @anim/5 Patented June 14, 1938 PATE-Nr OFFICE A v 2,120,381 v DEVICE Foa BURNINGLATOMIZED LIQUID Adolf Bargeboer, The Hague, Netherlands Application March 9,

1934, serial No. 714.791

In the Netherlands-March 14, 1933 3 Claims.

-This invention relates to a device for burning a mist of fuel, said mist being produced by pressure-atomizing. In devices of this type the ycombustion air flows directly around the spraying device to the flame and the ignition point of the flame is not stable.

Dependent on such factors as the draft, the spraying and the shape of the spraying nozzles in prior art devices, the flame formed floats as a cloud in the combustion chamber, making complete combustion impossible and causing the ame to become easily extinguished.

The object of the present invention isto eliminate these objections and is attained by providing inside the device, and directly around the spraying device, an air supply conduit or pipe. 'I'he combustion air flows outside this pipe through an element offering resistance to the flow oi' air,

such as a set of concentrically arranged screwv blades, bafes, perforated plates, or the'like. A quantity of air, which is regulated independently cf the combustion air, flows intol the inner pipe around the spraying device. This quantity forms only a smalll part of the combustion air. By exact adjustment of this quantity of inside air it is possible to give a stable shape to the flame and the combustion will begin at an adjustable short distance from the spraying device.

Preferably, the end of the inside air pipe is of an' obtuse conical or streamlined shape. An opening angle larger than 60 is desirable in most cases. A very stable flame formation results when an obtuse cone is fitted around the nozzle of the spraying device which forms, together with the conicallyshaped end of the inside pipe, a conemantle-shaped conduit for the inside air. More-` over, a slight super-pressure is developed at the tip of the spraying device instead of a depression or stagnant space which would otherwise arise at this point by the deflection of the combustion air ow from the tip of the spraying device. OW-

. ing to this arrangement, breaking back of the ame on the spraying device and sooting and blacking of the spraying device and the ignition electrodes are prevented.

Preferably, the width of the cone-mantle-v lspraying device with screw blades. These may be in the same or in the opposite direction to a screw fitted in the supply pipe for the combustion air.

In order to minimize the inevitable irregularities in the spraying ofv the fuel it is desirable to arrange the spraying device so that it may be rotatably adjustable in the inside pipe.

If an air flow resistance, e. g., a screw, is fitted in the pipe in the path of the combustion air, the inside air may be tapped oif ahead of-this resistance. A valve or the like may be usedto adjust the iiow. The air flowing through the conduit l mayv also be tapped oifthe main air pipe so that the air pressure in this conduit may remain constant. v

Figs. 1 and 2 are side elevations partly in section of two devices arranged .according 'to the invention. v

In Fig. 1, I is the motor driving the low-prese sureventilator 2 and the fuel pump 21. The air flows by way of the main supply pipe 3, throttle valve 4 to the combustion device 5. The latter consists of a tubular part 6 for the combustion air wherein inside pipe 1 is arranged for the inside air and is fastened by thesupports I6 to the cover |'I. These 'pipes form primary and secondary air conduits, respectively. The inside pipe 1 ends in the obtuse conical. part 2| having outlet opening 22. Inside of pipe 'I the spraying device 8 is surrounded by cone 30 which, together with the cone-shaped end 2| of pipe 1, forms a cone-mantle-shaped passage. The combustion air pipe 6 is provided with the screw blades 25 and y pipe 1 opens into thelchamber ahead .of it. The valve I4 is adjustable With respect to seat I5 of pipe I by means of screw 28 and button 29. The

fuel-supply pipes of the adjustable spraying device 8 are arranged in the cylindrical part I3 which is rotatable and shiftable in conduit I8 of cover I'I, so that the'spraying device is rotatably and shiftably adjustable with respect to the coneshaped part 2|.

The ignition transformer 26; leads 2'I and electrodes 24 are indicated in Fig. 1.

Fig. 2 shows a variation of the construction of Fig. l in which the inside air is tapped` off the` main air pipe 3 ahead of throttle valve 4 by means of pipe 3| and connection l. The inside air is adjustable by means of throttle valve 32 and the spraying device is adjustable with respect to-the cone-shaped end 2| of pipe 3U of the spraying device 8 land the entire pipe 'l may be shiftable in pipe 5.

Part of the combustion air some other place.

What I claim is:

1. In a device for burning a mist of atomized liquid fuel, a pressure spraying device 'for producing a mist of fuel, two air conduits coaxially arranged around said spraying device and opening substantially in the plane in which the fuel is discharged from the latter, the outside air conduit supplying air to support combustion, the inside air conduit supplying air to stabilize the flame, a pressure device supplying air to both conduits, baflie means within the outside air conduit forI offering resistance to the flow of combustion air therethrough to keep the air pressure of the air discharged from this conduit at the point of ignition at a lower value than the pressure of the air discharged from the inside conduit may be supplied at so as to secure different air velocities at the noz-A zle ends of said air conduits and thereby prevent the formation of a stagnant space at the ignition point adjacent the tip of the nozzle. .A

2. In a device for burning a mist of atomized liquid fuel, a pressure spraying device for producing a mist of fuel, two air conduits `coaxially arranged around said spraying device and opening substantially in the plane in which the fuel is discharged from the latter, the outside air conduit supplying air to support combustion, the inside air conduit supplying air to stabilize the fiame, a pressure device supplying air to both conduits, means including a valve for controlling the flow of air through said inside conduit, means within the outside air conduit for offering resistance to the flow of combustion air therethrough to keep the pressure of the air discharged from this conduit vat the point of ignition at a lower value than the pressure of the air discharged from the inside conduit so as to secure different air velocities at the nozzle ends of said air conduits and thereby prevent the formation of a stagnant space at the ignition point adjacent the tip of theA nozzle.

3. In a device for burning a mist of atomized liquid fuel, a pressure spraying device for producing a mist of fuel, two air conduitscoaxially arranged around said spraying device and opening substantially in the plane in which the fuel is discharged from the latter, the outside air conduit supplying air tosupport combustion, the inside air conduit supplying air to stabilize the name, a pressure device supplying air to both conduits, means in said inside air conduit for swirling the air therein, means including a valve for controlling the flow of air through said inside air conduit whereby a stable flame is produced at a point in close proximity to said nozzle and means within the outside air conduit for offering resistance to theflow of combustion air therethrough to keep the pressure of the air discharged from this conduit at the point of ignition at a lower value than the pressure of the air dischargedfrom the inside conduit so as to secure different air velocities at the nozzle ends of said air conduits and thereby prevent the formation of a' stagnant space at thevignitionl point adjacent the tip of the nozzle.

ADoLF BARGEBOER. 

